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Richard Floyd
05-05-2005, 07:07 AM
I've got a question for you guys, and I've done several searches but none have turned up quite the info I have been looking for. I know a few of you guys on here are real experts in the transmission swap area, so let me "pick your brains" for a moment:

First, here's why I'm curious - I'm looking at the 3rd gen Accord 2-door hatch as a candidate for SCCA ITB and NASA Honda Challenge H5 road racing. I used to race a 1st gen Integra in Honda Challenge and SCCA, but sold it, and now I'm looking at building a new car. The aternative to this car is the 1st gen CRX Si, but I worry that the car is a little underpowered compared to the 1st gen Teg and the 3g Accord. I just remember myself in the Teg and a friend in his Accord lapping all of the CRX's and 3g Civics at Lowes Motor Speedway a few years back, and I just don't want to be on the other end of that stick. So I'm leaning towards building an '88 Accord. (BTW: I don't want to build another Teg, and sold the first one, because it is completely outgunned in SCCA where it is classed against 2g CRX Si and 2g Integras, and has little to no chance of being reclassed any time soon)

Soooo, my question is this: What alternatives do I have in the final drive department? The Accord that I raced against had the factory FD and it, combined with the poor 4th and 5th gear rations, really wasn't ideal for road racing. Even on the long back stretch at Lowes, he never took it out of 4th as 5th gear was just too tall. Same at Roebling Road and Road Atlanta. I talked with him a couple of weends ago at a race and he mentioned that he really wanted to put in a different FD, maybe a 4.40 or something in that range. Unfortuantely for a lot of the older cars, particularly in the really short ratios (such as the 4.93 used in a lot of the 1g CRX race cars), the only choice is to have a custom FD made by Houseman for between $1200 - $1600. Too rich for my blood.

The rules state that the factory Accord gear box and all gears 1-5 must be factory, so legally I cannot swap a Prelude gearbox, or gears, nor can I install Integra gears into an Accord case. Mut be the Accord transmission. However, the FD ring and pinion are free.

Is there a better FD gear set used in another Honda product that will fit a 3g Accord? I think something along a 4.40 would be ideal to make 5th useable and give a little more grunt to 4th gear.

Any ideas?

Thanks in advance!

PhydeauX
05-05-2005, 07:50 AM
This is mixed up crap.. read below for my corrections. Sorry for the misinformation

You'll run into a little problem with that rule and changing the final drive then. On the counter shaft, the gears for first and second along with the final drive pinion are all cast as one piece, they can not be changed individualy. If it were possbile to change the FD with out having to swap the whole countershaft then the teg FD would fit your bill. The only thing you can do is use an efi gearbox if your not already or get a custom counter shaft with the factory first and second ratios on it.

andy

Richard Floyd
05-05-2005, 08:15 AM
The only thing you can do is use an efi gearbox if your not already or get a custom counter shaft with the factory first and second ratios on it.

You mean a tranny from a FI car as opposed to a carbed Accord, right?

Wow, that blows. Why in hell would they cast the pinion from the same peice as the 1st and 2nd gears?

Richard Floyd
05-05-2005, 09:42 AM
You'll run into a little problem with that rule and changing the final drive then. On the counter shaft, the gears for first and second along with the final drive pinion are all cast as one piece, they can not be changed individualy. If it were possbile to change the FD with out having to swap the whole countershaft then the teg FD would fit your bill.

OK, now I'm confused. I just remembered I have a Haynes manual for the '84 - '89 Accord (I used to have '87 and an '89 Accord sedans).

The diagrams showing the countershaft components and the mainshaft components show the first and second gears being separate pieces from the countershaft itself. The pinion gear itself is cast (or machined) into the end of the countershaft, though. Wouldn't the gears have to be removable from the countershaft in order for you to be able to replace the synchros between the gears. The diagram for the mainshaft however has first and second gears cast onto it. But as long as the 1g Teg ring gear will fit on the Accord diff carrier, and the 1g Teg countershaft will fit in an Accord box, this should work, right?

So the questions are:

Will a 1g Teg countershaft fit in an Accord box? (my guess is probably not but I have no idea)

Will a 1g Teg ring gear fit on a 3g Accord diff carrier? (maybe?)

If the ring gear will fit but the countershaft won't, could a skilled machinist modify the Teg countershaft to work? Or modify the Accord countershaft by attaching the Teg pinion to the end in place of the accord pinion?

...I do just happen to know a machinist that specializes in prototype odd-ball stuff, and his work is top notch. Plus, he works for Budweiser. He built the cage in my old racecar for the cos of the tubing plus 2 cases of cold ones! :)

rjudgey
05-05-2005, 01:15 PM
Can't you just swap the 1G teg internals into the 3G box, thats what i did, i'm sure they wouldn't pull your whole gearbox out just to check the ratios??? BTW the Lude box has tall gears as well so i'd stay clear, best bet is with Teg box internals.

Richard Floyd
05-05-2005, 01:54 PM
Can't you just swap the 1G teg internals into the 3G box, thats what i did, i'm sure they wouldn't pull your whole gearbox out just to check the ratios??? BTW the Lude box has tall gears as well so i'd stay clear, best bet is with Teg box internals.

I'd do that, except it's just illegal. Cheating may be rampant according to some, but I personally will come in 2nd legally before I'll cheat to win. Too much integrity and self respect, I guess.

PhydeauX
05-05-2005, 02:50 PM
/me goes and digs through the box of old transmission parts.


You and the haynes manual are correct. The first and second gears are removeable from the countershaft. Its the main shaft that they can't be removed from.

My appologies it's been 2 years since I had one of those trannies apart, I should have looked before I spoke.

Back to more useful information:

You should beable to use a teg final drive in your accord transmission. I believe that you can use any ZC countershaft and final drive but you would have to look that up to verify. (If I can't remember correctly something I did 2-3 years ago I wouldn't trust something I think I read 2.3 years ago). Basically if it works in a 1g teg it should work for you. That would include LSDs if you are allowed to run them. Also I'm not sure you are allowed to swap cases leaving the internal gears alone but if you can swap to an integra case. It has better oil passages to the 5th gear which makes it last conciderably longer. There is a blanked hole in the accord case that could be drilled out to match the oil passage in the teg case if you'd rather stick to an accord part. If you look at the 5th gear side of an accord and teg case you will see what I am talking about.

Anyhow to directly answer your questions:

Will a 1g Teg countershaft fit in an Accord box?

Yes, it fits perfectly.

Will a 1g Teg ring gear fit on a 3g Accord diff carrier?

Yes, the carriers are interchangable so if you can get your hands on a 1g teg LSD that that would work as well.

andy

PhydeauX
05-05-2005, 02:56 PM
I figured this migth be of some use to you. I compiled it when I was doing research for the teg tranny swap. I don't believe this ever made it into the faq.

86 prelude 87 accord 87 integra
Carbed DX LX-i

Forks
1-2 shift fork 24221-PC8-920 24221-PC8-920 24221-PC8-920
3-4 shift fork 24211-PC8-J00 24211-PC8-J00 24211-PC8-J00
5th shift fork 24201-PB6-910 24201-PB6-910 24201-PB6-910
5th fork shaft 24271-PC8-930 24271-PC8-930 not listed

Differential
diff bearing 91005-PC9-008 91005-PC9-008 91005-PC9-008
diff houseing 41310-PC8-921 41310-PC8-621 41310-PG9-600
diff side gear 41221-PC8-912 41221-PC8-040 41221-PC8-040
diff pinion 41341-PC8-030 41221-PC8-030 not listed
pinion shaft 41321-P21-A00 41321-P21-A00 41321-P21-A00

Counter Shaft
shaft 23220-PC8-662 23220-PC8-671 23220-PG9-600
needle bearing 91101-PC8-J01 91101-PC8-J01 91101-PC8-J01
ball bearing 91004-PC8-J01 91004-PC8-J01 91004-PC8-J01
second bearing 91106-689-008 91106-689-008 91106-689-008
first bearing 91105-PB6-008 91105-PB6-008 91105-PB6-008
first gear 23421-PB6-010 23421-PB6-010 23421-PB6-010
second gear 23432-PC8-325 23432-PC8-J20 23432-PG9-305
third gear 23471-PC8-910 23471-PC8-J21 23471-PG9-600
fourth gear 23481-PC8-000 23481-PC8-J21 23481-PG9-600
fifth gear 23461-PC8-960 23461-PC8-J21 23461-PG9-600
3rd 4th spacer 23917-PB6-000 23917-PB6-000 23917-PB6-000

Main shaft
shaft 23211-PC8-962 23211-PC8-J21 23211-PG9-010
ball bearing 91002-PC8-J02 91002-PC8-J02 91002-PC8-J02
needle bearing 91103-PC8-018 91103-PC8-J01 91103-PC8-J01
third bearing 91104-634-008 91104-634-008 91104-634-008
fourth bearing 91104-634-008 91104-634-008 91104-634-008
fifth bearing 91104-634-008 91104-634-008 91104-634-008
third gear 23442-PC8-315 23442-PC8-J20 23442-PG9-305
fourth gear 23451-PC8-000 23451-PC8-J21 23451-PG9-600
fifth gear 23581-PC8-960 23581-PC8-J21 23581-PG9-600

Reverse
idler gear 23540-PC8-J01 23540-PC8-J01 23540-PC8-J01
23540-PC8-000 (2 parts listed for lude)
shaft 23261-PC8-000 23261-PC8-000 23261-PC8-000

That cross refrences all the accord, lude, and teg part numbers for most of the transmission parts. I don't have the syncro's listed in there but they are the same. The main thing to note is that the bearings are the same on the shafts for both the accord and teg.

andy

PhydeauX
05-05-2005, 03:26 PM
I'm whoring it up right now but I believe all this information is better presented in seperate posts.

Anyway. I did a quick google search and found where I had previously read about the ZC trans swap. Take everything with a grain of salt as I can't confirm any of this.

This is the original link http://hybrid2.honda-perf.org/tech/4gtech.html

And this is the relevant paragraph:


The Si transmission is the best choice available. Both the Si and DX transmission bolts right up and keeps the install simple. The DX transmission will sacrifice performance for better fuel mileage and lower freeway rpms. The ZC tranmission has a close ratio 1-5th gear, but a long final drive, making the best transmission still the US Si. For the ultimate acceleration make a Si/ZC hybrid transmission, by taking the Si final drive and put it in the ZC transmission. Or you can do it the other way around, ZC 1-5 in a Si transmission case. Either way, expect 80mph to turn 4300 rpms. However, the ZC transmission requires you to use ZC or 90-91 Integra axles, and a ZC or 86-89 Integra intermediate shaft. Because these axles are equal length, many users report a reduction in torque steer.

There is a dead link on the page to the process for the swap. Here is is if you wish to read it. http://hybrid2.honda-perf.org/tech/zcsifdswap.html

It makes me think that the civic Si final drive should work in the accord case. This is because I believe the ZC trans the integra trans are more or less the same thing. I don't remember where I came up with that information so I may be way off base (and I have no way to cross-reference JDM parts).

I'm not sure how much diference that all makes because the usdm integra trans is reported to be 4.21 where the civic Si is 4.25 (the jdm zc trans they are talking about is 3.88, similar to the accord's). If that is the case though and you can use the civic final drive then that opens up several aftermarket options.

andy

dillirk
05-09-2005, 10:55 AM
From what I remember from my teg trans mod a year ago all you have to do is put all the accord counter shaft parts on the teg counter shaft and install the teg diff. the diffs are identical so save yourself a few minutes and just swop the whole thing instead of taking the gears off and swopping them.

Slipknotcraig133
05-09-2005, 01:34 PM
So if we could use the si final drive what about axles do ours work?

PhydeauX
05-09-2005, 05:13 PM
They should, they are splined the same as the 1g teg. That is if the 1g teg tranny is similar to the ZC tranny which we still don't know for sure. It will probably take some one to actually try it, or maybe someone with more expierence with 1g teg and zc trannies. I've pretty much exhausted every search string I could think of on google with out finding anything definite.

andy

Slipknotcraig133
05-09-2005, 08:28 PM
I might try im not sure i have a friend that had a 90 hatch that he converted to an si and he blew out one tranny and i think i will take a look at the final drive and mabye see if it will work.

PhydeauX
05-10-2005, 12:33 PM
Go for it. That would be the best if you could find a blown trans, rather then waste the money on a good Si trans only to find out that it doesn't quite fit. It doesn't matter even if the final drive is blown as well, it can always be test fit to prove the theory then a good one purchased.

If you don't feel like going through the trouble of testing it and he is just going to junk that trans I'd like to get my hands on the final drive for a test fit. I've got a spare disassembled tranny already. Unfortunately I'm broke, just like everyone else so I can't offer much more then shipping costs. But I wouldn't care if it was cracked or missing teeth since I would just stick it in my junk case to see if everything lined up and the swap were possible. If you wanted I would return it once I have my results but I can't offer any more collateral then good faith.

andy

Slipknotcraig133
05-10-2005, 05:27 PM
Allright. Yea i talked to my friend with the tranny and he said if i wanted it i could try it. But the only reason i dont really want to try it is i dont want to rip my car apart. If i can get the tranny before i get new wheel bearings i will try my self but if i cant then i will send you the final drive and let you have at it.